A year ago, Nicola Sturgeon marked Robert Burns’s 25 January birthday by posting a video celebrating his poetry, praising Scotland’s national bard for his “enduring values of equality, inclusion and internationalism” and inviting Scots to toast his memory at that evening’s Burns Night parties.

After an intervening year that has seen the rise of #MeToo, Scotland’s first minister may feel a need to insert a feminist caveat or two as she gives the address on Thursday at a Burns supper hosted by the SNP’s Govan branch, after Liz Lochhead recently called Burns “Weinsteinian” and “a sex pest”, and prompted a controversy that has raged in the Scottish press for the past fortnight.

Ahead of her talk on Burns and Women next week, Lochhead, the poet, playwright and former makar previewed her speech, in which she calls Burns a “sex pest” and drew attention to a 1788 letter to a friend in which he bragged of giving his lover Jean Armour a “thundering scalade [a military attack breaching defences] that electrified the very marrow of her bones”, and said he “fucked her until she rejoiced”.

For Lochhead, this “disgraceful sexual boast … seemed very like a rape of his heavily pregnant girlfriend. It’s very, very Weinsteinian.” After her comments were aired on the BBC, Lochhead received support from Robert Crawford, whose biography of Burns quotes the letter, and who argued in the Herald that “what he presents as ... exclamations of pleasure may well have been cries of pain”.

Burns did have “his Weinstein moments”, Crawford agreed, and “feminists are right to subject [him] to scrutiny” when he comes across as “an 18th-century buck showing off [to] his male cronies”.

Also in Lochhead’s camp is the author and critic Stuart Kelly, who on Burns’s birthday last year highlighted the bragging letter in a Guardian article that questioned “why we all raise a glass ... to the boor-bard of Scotland”. “There is an image of Burns,” Kelly wrote, “a bit of a rascal, a bit roguish, a naughty roister-doisterer – who nevertheless produced some of the greatest love poetry in our language … But here’s another r-word. Rapist.”

However, Lochhead has been criticised by Burns scholars such as Gerard Carruthers, who said there was “no good evidence” that the national icon was a rapist and complained of an approach that “refracts everything through our 21st-century presentism, essentially judging history by the ephemeral journalistic stories of today”. Wilson Ogilvie similarly argued that “Burns was not lily-white in his attitudes towards women”, but – given the “huge differences” between his world and Weinstein’s – “Miss Lochhead has gone a bit over the top” in comparing them.

Catherine Czerkawska, author of a novel about Armour as well as a Burns expert, told the Scotsman comparisons between the poet and film producer were “invidious” and said “to label the events described in the letter as rape is to oversimplify a relationship of great complexity”.

Lochhead herself, ironically, found herself defending Burns during his 250th anniversary festivities in 2009, when she responded to charges that he was “a racist, misogynist drunk” – and hence no role model for Scots – by calling such arguments “complete rubbish. It’s not relevant to his poetry, it’s not the point. We don’t look to him for a way to live our lives … Of course I wouldn’t look to him as a feminist role model, but he’s not a role model, he’s a great poet.”

In an overlooked part of her recent remarks, Lochhead made the same point again, though rather more mutedly. Does the fact that Burns was a sex pest “mean he isn’t worth reading?” she asked, answering that “it’s not really relevant”.

Arguing that an author’s attitude to and behaviour towards women is irrelevant is questionable, though, when he’s best known for love poems – and when politicians are holding up his “values” as admirable as well as his verse.